Heliopan 39mm uv ultra violet haze glass filter. the uv filter, also known as a haze filter, is not only an excellent universal filter for visually improving photographs with all film types, but it can always stay on the lens for protection from dust, fingerprints, moisture, etc. and for use under extreme conditions it absorbs the short wave portion of the spectrum so under hazy conditions a clearer reproduction of the scene is possible. The loss of sharpness caused by uv rays and the bluish tones common in infinity scenes are eliminated with the colorless uv filter. An exposure correction is not required. Vendor Part # 703901